Large utility station transformers are an integral part of modern day electricity transmission and distribution systems. These critical pieces of equipment represent a tremendous investment of time and cost on the part of the utility companies. Additionally, failure of such transformers can result in many millions of dollars worth of economic damage, even if such failures are only for a short duration.
As a result of the large investment and high cost of any down time, transformers are periodically monitored for potential partial discharge activity within. Typically, such “spot” monitoring, as it is known, is accomplished by temporarily equipping the external casing of the transformer with a plurality of sensors that sense acoustic noise caused by a partial discharge or other event inside the transformer. This spot monitoring is conducted intermittently, on request, and usually over a period of several days or even weeks.
Several drawbacks with such prior techniques exist. First, because the external sensors are mounted on the outside of the transmission case and locate partial discharge events via triangulation, accuracy is diminished. Second, the monitoring only occurs at the relatively infrequent periods that the sensors are utilized. Third, the process of spot monitoring is typically sold to the utility companies by third party entities, and thus tends to be relatively expensive.
It is an object of the invention to provide a reliable and relatively inexpensive method to continuously monitor partial discharge events in transformers and the like.
It is an object of the invention to provide instantaneous and continuous monitoring and feedback of partial discharge event information within transformers and the like.
It is an object of the invention to be able to compensate for environmental variations within the transformer that could affect the detection of partial discharge events.
The foregoing and other objects of the present invention will be clear upon review of the following description and drawings.